Device Service: Decouple Wake Lock from //content

device/wake_lock/public/interfaces/wake_lock_context.mojom

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+module device.mojom;
+
+import "device/wake_lock/public/interfaces/wake_lock_service.mojom";
+
+// Context in which WakeLockService instances operate.
+interface WakeLockContext {
+  // Gets a WakeLockService within this context.
+  GetWakeLock(WakeLockService& wake_lock);
+
+  // Test-only method that returns whethere a wake lock is currently active
+  // within this context.
+  HasWakeLockForTests() => (bool result);
+};